RoboLab on a fast computer

I just had a wierd problem. I tried to program an RCX from RoboLab running on a new 3 GHz Hyperthreaded PC, and couldn't get the communication going
from the IR tower to the RCX. I went back to my old 500 MHz P3, and it worked fine. Sounds like a timing issue. Is there a version of RoboLab that works with fast computers? Is there a way to make RoboLab 2.5.2, the version I have, work on fast computers?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.